An embodiment of the invention is related to lifting systems that can raise and lower personnel and equipment up to and down from an upper level of a tall structure such as a building, a cellular network communications antenna tower, a wind based electricity generator tower, or an off-shore oil/gas platform. Other embodiments are also described.
Lifting systems that can be deployed to a given job site so as to raise and lower a desired load adjacent to a tall structure have been described in U.S. Pat. Nos. 7,395,899 and 7,537,087 of Marvin M. May (“My Previous Patents”) both of which are incorporated herein by reference. These systems include a closed loop lifting cable to which a load is attached and which is rotated by a traction winch to raise or lower the load. Several horizontal load position control mechanisms are also described that allow the suspended load to be moved sideways, independently from the raising and lowering capabilities.